1. Field of the Invention:
The present invention relates generally to exhaust systems for internal combustion engines, and more particularly, to a method and apparatus for reducing back pressure associated with such exhaust systems. p 2. Description of the Prior Art:
Vehicles powered by internal combustion engines typically include an exhaust system for expelling exhaust gases from the engine. For example, the exhaust system of a conventional automobile often includes an exhaust pipe connected at one end to the exhaust manifold of the engine and coupled at the opposite end to a muffler used to deaden the noise and vibration accompanying the escaping hot exhaust gases. More recently, emission control devices such as catalytic converters have been interposed between the engine and the muffler to reduce hydrocarbon and carbon monoxide pollutants from the exhaust stream. The outlet of the muffler is typically connected to a tailpipe which directs the exhaust gases toward the rear periphery of the underside of the automobile to prevent exhaust fumes from collecting below the underside of the vehicle. The tailpipes of some known models of automobiles also include a resonator to provide for optimum tuning characteristics of the exhaust system.
Back pressure developed by the exhaust gases within the exhaust system can result in a reduction in the efficiency of the expulsion of exhaust gases from the combustion chambers of the engine. Thus, an increase in back pressure developed by the exhaust system may result in a decrease in engine performance and a decrease in fuel efficiency. Accordingly, manufacturers of automobiles and other vehicles usually attempt to design such exhaust systems so as to present as little back pressure to the engine as possible. However, despite the attempts by such manufacturers to reduce the back pressure associated with automotive exhaust systems, such exhaust systems nonetheless continue to develop substantial back pressure which can degrade engine performance and fuel efficiency.
Accordingly, an object of the present invention is to improve the performance and fuel efficiency of an internal combustion engine.
Another object of the present invention is to reduce back pressure developed by exhaust gases within an exhaust system for an internal combustion engine.
Still another object of the present invention is to provide a method and apparatus for reducing back pressure developed by exhaust gases within an automotive exhaust system without adversely affecting the sound dampening and emission control functions of the exhaust system.
Yet another object of the present invention is to provide a method and apparatus for reducing back pressure developed by exhaust gases within an automotive exhaust system without adversely affecting the optimum tuning characteristics designed into the exhaust system by the manufacturer of the vehicle.
A further object of the present invention is to provide an apparatus which can be easily and inexpensively added to the conventional exhaust systems of both newly manufactured and pre-existing automobiles in order to reduce back pressure developed by exhaust gases within such automotive exhaust systems.
These and other objects of the present invention will become apparent to those skilled in the art as the description thereof proceeds.